The negative energy is partially recoverable and reusable
To meet our needs, we consume energy as if it were
inexhaustible, we produce what we need and evacuate to heat everything
that hinders our comfort.
We behave as if we were unable to manage energy, taking only what we need and setting aside the remainder for later use.
The production of mechanical energy through at least two stages :
Denis Papin has shown that between A and B, we can increase the potential energy of steam contained in an enclosure by an external supply of heat energy.
Then James Watt has shown that between B and C we can convert the potential energy of steam into mechanical energy.
It is essential to distinguish and separate these two phases : between A and B the goal is to increase the potential energy of a fluid by an external supply of energy, while between B and C the goal is to transform the potential energy of the fluid into mechanical energy.
The steam machine separates these two phases and maintains a reserve of potential energy available in the form of steam under pressure.
The internal combustion engines combine the two phases without keeping in time the potential energy of gas under pressure. The principle of internal combustion engine is well suited to convert with a good efficiency the energy for a constant load, to propel a ship or pull a plow for example, but these engines have an efficiency that goes from low to zero when the load is variable, becomes zero or negative.
As in the example of the steam engine, between A and B we must use an external energy to increase the potential energy of the fluid inside the high pressure chamber. This is no longer subject to the requirements of end use and can therefore be achieved by seeking the best performance conditions, it can be managed by a computer.
In B an adequate reserve of potential energy is preserved in time
Between B and C, we must use a reversible mechanism to transform the potential energy of fluid into mechanical energy and controlling motion.
This approach is valid for many applications of internal combustion engines and electric motors, in fact, for most applications that use a braking system, including the "engine brake" to control the movement of vehicles, elevators, handling charges.
Le system may be part of the transmission.
The efficiency of a hydraulic or pneumatic accumulator is close to 100%, the efficiency of a hydraulic Motor/Pump of this type is about 90% ; it is realistic to provide a recycling of the negative mechanical energy from 70 to 80 %.
The environmental impact is not negligible.
When fossil fuel is the source of mechanical energy used, for each Joule of mechanical recycled instead of being wasted as heat by braking, you must add at least two Joules that have been converted into heat to generate the new mechanical Joule.
The figure shows a hydraulic variable displacement Motor/Pump controlled by a simple centrifugal device.
The device is capable of controlling a rotation speed, is adjustable and compatible with non-lubricating fluid such as water
Depending on the applied load, the device behaves as a motor in consuming power of the hydraulic accumulator (acceleration) or as a pump in returning negative energy into the hydraulic accumulator (deceleration).
A simple pump like the one used in high pressure cleaners, works intermittently to maintain a minimum reserve of energy in the hydraulic accumulator.
- To heat a house
intelligently we must first achieve effective insulation of the
- To produce a unit of mechanical energy it takes at least 3 units of fossil energy : recycling mechanical energy is to begin at the beginning, as a insulate a building.
Logical reasoning :
Using the same fluid in high and low pressure chambers, the principle of the steam engine is better suited to control the movement of a variable load, zero or negative, because a potential energy of the fluid is conserved in time and the transformation mechanism between B and C is reversible.
In all applications to control movement, when a negative energy from deceleration or descent of a load is involved or when the load is mostly variable, it is necessary to have a first chamber containing a fluid under high pressure connected via a motor able to work as a pump, to a second chamber containing the same fluid under low pressure. Between the motor able to work as a pump and the use of energy, the transmission mechanism should be reversible.